Methods of making fiber waveguides from multilayer structures

1. A method for forming a fiber waveguide, the method comprising:

rolling a multilayer film into a structure having a spiral cross-section, wherein the multilayer film comprises at least two layers of materials with different refractive indices at a wavelength λ, the materials being thermomechanically compatible with each other; and

forming a fiber waveguide from the structure, the fiber waveguide having a core extending along a waveguide axis and a portion surrounding the core having a spiral cross-section, the refractive index of the materials and a thickness of each of the layers having values such that the portion of the fiber waveguide having the spiral cross-section is structured to guide radiation at λ in the core along the waveguide axis,

wherein the forming the fiber waveguide comprises drawing a fiber preform derived from the structure having the spiral cross-section.

2. The method of claim 1 , wherein the layers comprise a layer of a first material and a pair of layers of a second material sandwiching the first material layer.

3. The method of claim 1 , wherein the different materials comprise a first material comprising a glass and a second material comprising a polymer.

4. The method of claim 1 , further comprising:

disposing at least a first layer of a first material on a second layer of a second material different from the first material to form the multilayer film.

5. The method of claim 4 , wherein the first material is disposed on both sides of the second layer.

6. The method of claim 4 , wherein the second material is a polymer.

7. The method of claim 6 , wherein the polymer comprises PES or PEI.

8. The method of claim 4 , wherein the disposing comprises sputtering.

9. The method of claim 4 , wherein the disposing comprises evaporating.

10. The method of claim 4 , wherein additional layers are disposed on the first and second layers to form the multilayer film.

11. The method of claim 4 , wherein the first material is a glass.

12. The method of claim 11 , wherein the glass is a chalcogenide glass.

13. The method of claim 1 , wherein the multilayer film is rolled around a rod to form the structure having the spiral cross-section.

14. The method of claim 13 , wherein the rod is hollow.

15. The method of claim 13 , further comprising consolidating the structure having the spiral cross-section to form the preform.

16. The method of claim 15 , wherein the consolidating comprises heating the structure having the spiral cross-section.

17. The method of claim 16 , wherein the consolidating comprises heating the structure having the spiral cross-section under vacuum.

18. The method of claim 13 , further comprising removing the rod from the preform prior to the drawing.

19. The method of claim 18 , wherein the rod is removed by chemically etching.

20. The method of claim 1 , wherein the structure having the spiral cross-section comprises a core surrounded by the multilayer film.

21. The method of claim 1 , where the core is a hollow core and the portion having the spiral cross-section comprises multiple layers corresponding to the multilayer film.

22. The method of claim 1 , wherein the multilayer film comprises a polymer film and a layer of a glass deposited on the polymer film.

23. The method of claim 1 , wherein the multilayer film comprises a pair of amorphous materials that have substantially different refractive indices.

24. The method of claim 23 , wherein one of the amorphous materials is an inorganic glass.

25. The method of claim 24 , wherein the other one of the amorphous materials is a thermoplastic polymer.

26. The method of claim 24 , wherein the inorganic glass is a chalcogenide glass.

27. The method of claim 26 , wherein the chalcogenide glass is As 2 Se 3 .

28. The method of claim 27 , wherein the thermoplastic polymer is polyethersulfone or polyetherimide.